Muso-futurist journalist Simon Reynolds defined the music of Tortoise for them several years ago: they’re “post-rock”, they’re “using rock instruments for non-rock purposes”. Now, that’s broad. He means bands that conflate the symphonic, the swingin’, and the rockin’, but you really have to torture that bit of language to deliver a sense of newness based on that definition. Unless musicians are slicing eggs using their guitar strings and ladling soup out of up-ended snare drums, the major work in the field of “non-rock purposes” was done long ago by Yes, Faust, King Crimson, Henry Cow, Can, and gatekeeper Frank Zappa, to name only the bigger, legendary guns. Nonetheless, after several well-regarded albums that had left me cold, Tortoise’s new album has an out-of-whack feel that alerts me to the fact that something eccentric is going on.

Leaders/percussionists John McIntyre and Doug McCoombs have played with many other groups—McIntyre plays marimba on the latest Stereolab album. They claim so many inspirations that I feel lazy saying Standards works because it’s direct and catchy at a relatively simple level—art-rock that’s literally hummable. Claiming a million influences isn’t as impressive as it used to be: long ago, Zappa updated Edgard Varèse, and Henry Cow cribbed from Bartok and Stockhausen, while Tortoise takes from Zappa and Henry Cow. But this heavily conflicted mix of orchestrated rock instrumental extensions are capped, for once, by themes that are perky and airy. The melodies have been fitted out in terms of which processed effects would be most memorable in themselves—a gambit good for ambient music and modern R&B productions alike.

It’s the stuff beneath the melodies that feels funny—it’s stunted. Trying to piece all this together, I whistled the sinuous melody of “Monica’’ a lot—because McCoombs’ counter-rhythmic drumming hooked me from below. “Six Pack” strongly suggests one of Zappa’s rare lyrical, playful tunes—it’s a “Peaches En Regalia” for our time. But there’s no horn for a lead voice, and after his opening squall on “Seneca”, guitarist Parker steps back into the textures. Rhythmically, the whole album moves like a crabwalk. No band with three drummers, three bassists, and two guitarists will rock out or get funky or swing. They have no choice but to orchestrate, especially with a vibraphone mallet in nearly everyone’s hand—gotta keep out of each other’s way somehow.

I’ve seen Parker play live with Tortoise and Isotope 217, and can attest that his playing destabilizes the synthesized textures and effects that surround him. But he isn’t much of a soloist; he lives for texture, just like his bandmates. Parker refuses the central leadership role that guitarists Zappa and Fred Frith took in their own bands, which may suggest why Tortoise’s concept feels more cerebral than it really is. The texture fetish is to the good this time. It isn’t every band that lets the vibraphone and marimba dominate their synthesizers and guitars, which lets the ambient noodling practically bleed spaciness.

This music is the sort that causes rockers to go back and forth, as easy to pick apart as to enjoy. But ultimately, Standards is Tortoise’s Fragile or Hot Rats—the sort of successful artwork that tells you a band’s concept is peaking. Would there were more to come, but it took them several albums to get around to producing even a bit of memorable music. So is this a new stage, or an ending?